David Alfaro Siqueiros' controversial mural was unveiled 80 years ago in Los Angeles, then quickly whitewashed. Now his gem is back.

It has taken 80 years, but Los Angeles today does honor to its history. After a painstaking rehabilitation, a long-hidden mural by David Alfaro Siqueiros will be unveiled.

The mural has a rollicking history. It was once the center of controversy, and then it was shrouded for decades. Siqueiros was one of Mexico's great muralists — ranked with Jose Clemente Orozco and Diego Rivera. His radical politics and his bold use of color and arresting imagery won him renown. An ardent Stalinist, he conspired to murder Leon Trotsky after Trotsky settled in Mexico City. That plot failed, but the Mexican government tired of Siqueiros, and he was exiled, settling for a time in the United States. In 1932, while in Los Angeles, he painted three murals here, including "America Tropical" for a rooftop beer garden overlooking Olvera Street downtown.

The original unveiling of "America Tropical" was not exactly what its sponsors had hoped for. The mural's central image is of a Mayan peasant hung on a cross, with an eagle — similar to those Siqueiros had seen on American coins — perched above. It shocked viewers, and a nervous city leadership reacted as insecure leaders often do. Barely six months after the mural was first seen, it was painted over, literally whitewashed.

A new generation of Los Angeles leaders has resurrected Siqueiros' work. The original colors would have been difficult to replicate — no color photographs of the original mural exist — and they have faded a bit, but perhaps that too is appropriate, as the arguments that caused so much consternation at the time also feel less pronounced today. In fact, one delicious aspect of the mural's return is that it was sponsored in part by the city government, which recoiled at the original, and in part by the Getty Foundation, whose patron was just the sort of capitalist the artist so vehemently deplored.

Los Angeles once flinched at "America Tropical." Tremulous leaders reached for censorship, shamefully covering up a work of consequence. Happily, a stronger, more secure generation — including politicians and capitalists — has revived Siqueiros' work and resuscitated this gem. The mural and its viewing center open Tuesday, 80 years to the day after it was initially unveiled.